1. Field of the Invention
The present invention relates in general to mobility management in a wireless communication network, and more particularly to a method for detecting and reducing ping-pong handover effect of a cellular network.
2. Description of the Prior Art
In a cellular network (e.g. the GSM system), the ping-pong handover is a very common phenomenon to degrade the network performance. The ping-pong handover means handover to and fro between a cell pair frequently. The ping-pong effect occurs due to the frequent movement of mobile units between the cell pair, or high signal fluctuation at the common boundary of the cell pair. Since the ping-pong handover increases the times of handover and thus the loading of the network, it is necessary for network operators to reduce this undesirable effect. However, the conventional technology does not provide a systematic and objective solution for the operators to find the cell pair suffering from the ping-pong effect, so it depends on the subjective experience of the operators or the try-and-error way to handle this problem. Usually, this approach would cause inefficiency and failure.